Collaborative Research RUI: Examination of the Effect of Templating Agents on the Size, Shape and Chiral Recognition of Bifurcated Amino Acid Based Amphiphilic Molecular Assemblies

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With the support of the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry, Eugene Billiot, Fereshteh Billiot and Mark Olson of Texas A&M University Corpus Christi (TAMUCC), along with their collaborator Kevin Morris at Carthage College, will synthesize and characterize a novel class of “branched” amino acid-based surfactants. The goal of the research is to understand the molecular factors responsible for the aggregation and self-assembly of these molecules into structures that will interact with and recognize molecules of biological importance. Synthesis of the surfactants will use a green chemistry approach where materials will be prepared from amino acid-based starting materials instead of potentially hazardous polyaromatic hydrocarbons. Furthermore, since the surfactants are amino acid-based, they are expected to be biocompatible. The research will help fill a void in the current knowledge base that is critical for the proper design and selection of more efficient chiral selectors. In addition, since enantiorecognition of the systems under study is based upon amino acid-scaffolding, the knowledge gained from these studies will be potentially transferable to other amino acid-based systems such as proteins. This project is a collaboration between two primarily undergraduate institutions, with one of those two institutions, TAMUCC, being a Hispanic-serving institution (HSI). Thus, the research to be funded by this grant will serve as a tool for the research team to recruit, train, and mentor students from underrepresented and economically challenged backgrounds and to encourage these students to pursue post baccalaureate degrees in science.The research is focused on investigating and elucidating the factors responsible for (a) self-assembly, (b) function, (c) higher ordered structure and (d) molecular recognition of amino acid-based macromolecular assemblies (AABMAs). A comparison of the properties of “linear” AABMAs to novel “bifurcated” AABMAs will be made and how they are affected by factors such as surfactant concentration, surfactant type (linear vs bifurcated), pH, and type of counterion/templating agent affect the size, shape, physical properties, and enantiomeric recognition of AABMAs. The AABMAs will be studied in both their monomeric and polymeric forms. The AABMAs micelles will be crosslinked by exposure to Co60 gamma radiation or 185 nm vacuum UV radiation. The effect of pH, counterion/templating agent, and surfactant concentration on polymerization, self-assembly, function, higher order structure and molecular recognition will be studied. A variety of techniques such as nuclear magnetic resonance (NMR), fluorescence, Small Angle Neutron Scattering (SANS), small angle X-ray scattering, cryo-transmission electron microscopy, dynamic light scattering methods, as well as capillary electrophoresis (CE) will be utilized to learn more about the physical properties of the AABMAs formed. Thermodynamic studies will be conducted to yield insight into the binding interactions between the chiral molecular recognition units of the surfactants/polymer micelles and the chiral analytes that will be targeted for chiral separations using titration microcalorimetry.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.